Dong-ju, often teased for being tone-deaf, joins a high-school choir for one reason. She wants to stay close to Min-soo, the only boy who doesn’t make fun of her when she sings off-key. However, to her disappointment, Min-soo turns over his accompanist position to Dong-ju and leaves for Japan to study.
Ten years later, Dong-ju meets Min-soo again at a high-school reunion, and her crush on him reignites. To impress Min-soo desperately, Dong-ju enrollers herself in a private vocal lesson and begins hard training under Shin-hong, the eccentric teacher, who is aspiring to be recognized as a serious singer himself. Shin-hong and Dong-ju work day and night with one mission, and their time together teaches them more about life than music.